Maniphest T76003

VR scene inspection - rendering artifacts on geometry only occluded for one eye with viewport denoising
Closed, ResolvedBUG

Assigned To
Peter Kim (muxed-reality)
Authored By
Zsolt Stefan (zsoltst)
Apr 22 2020, 5:17 PM
Tags
  • BF Blender
  • EEVEE & Viewport
  • Virtual Reality
Subscribers
Ankit Meel (ankitm)
Clément Foucault (fclem)
Julian Eisel (Severin)
Piotr Adamowicz (madminstrel)
Richard Antalik (ISS)
Zsolt Stefan (zsoltst)

Description

System Information
Operating system: Windows-10-10.0.18362-SP0 64 Bits
Graphics card: GeForce RTX 2080 with Max-Q Design/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 442.19

Blender Version
Broken: version: 2.83 (sub 13), branch: master, commit date: 2020-04-20 02:11, hash: rB23bb42a06e28
Worked: -

Short description of error
Trying out the new VR scene inspection feature, I noticed the following rendering artifact:

  • There is a faint duplicate of objects in the foreground visible to the right and to the left (depending on which eye) in front of other objects if Eevee viewport denoising is enabled.

Basically what seems to happen, is that the part of the scene that is occluded by an object in the foreground from the perspective of one eye but is visible from the other eye, is not rendered (or denoised) the same way as the rest of the scene. This goes for both eyes. This partly occluded area looks somewhat different, more pixelated, maybe a bit darker and surface reflections look different.

On a side note, the BlenderXR implementation from Marui plugin doesn't have this problem.

Exact steps for others to reproduce the error

  • Activate the VR inspection addon.
  • Start VR session on any scene.
  • Renderer should be Eevee, with viewport denoising turned on.
  • Look at an object in the foreground, while having some other objects behind it, further away.

Related Objects

Event Timeline

Zsolt Stefan (zsoltst) created this task.Apr 22 2020, 5:17 PM
Zsolt Stefan (zsoltst) added a comment.Apr 23 2020, 4:40 PM

Here's how it looks like. To the left of the lamppost is this weirdly rendered area.

Richard Antalik (ISS) added a subscriber: Richard Antalik (ISS).Apr 23 2020, 7:19 PM

@Zsolt Stefan (zsoltst) is this reproducible without VR headset? I don't have one and I am really not aware of this is possible without one.

Zsolt Stefan (zsoltst) added a comment.Apr 24 2020, 11:38 AM

@Richard Antalik (ISS) The bug can only be seen in the VR session, so you'd need a way to emulate a VR headset. An internet search led me here: https://docs.microsoft.com/en-us/windows/mixed-reality/using-the-windows-mixed-reality-simulator , this might work.

Eitan Traurig (EitanSomething) added a project: EEVEE & Viewport.May 5 2020, 4:16 PM
Julian Eisel (Severin) triaged this task as Low priority.May 18 2020, 5:16 PM
Julian Eisel (Severin) added a subscriber: Julian Eisel (Severin).

Would consider this a low-priority issue. After all it's a visual only glitch, and a very small amount of users will ever run into it I think. This might also be hard to debug I'm afraid.

Ankit Meel (ankitm) changed the task status from Needs Triage to Confirmed.May 19 2020, 10:48 AM
Ankit Meel (ankitm) added a subscriber: Ankit Meel (ankitm).
Bastien Montagne (mont29) changed the subtype of this task from "Report" to "Bug".May 27 2020, 11:43 AM
Julian Eisel (Severin) added a project: Virtual Reality.Jun 19 2020, 4:15 PM
Julian Eisel (Severin) moved this task from Backlog to Bugs & Known Issues on the Virtual Reality board.Jun 19 2020, 4:21 PM
Clément Foucault (fclem) added a subscriber: Clément Foucault (fclem).Jun 28 2020, 12:23 AM

@Julian Eisel (Severin) Is that because you render both eye with the same GPUViewport? Thus having only one history target that is constantly being swapped for each eye. If so I would recommend duplicating the GPUViewport to avoid this but I see that it would increase VRAM consumption quite a bit.

Clément Foucault (fclem) moved this task from Backlog to Known Issues on the EEVEE & Viewport board.Jun 28 2020, 12:23 AM
Piotr Adamowicz (madminstrel) added a subscriber: Piotr Adamowicz (madminstrel).Jun 28 2020, 7:02 PM

Look, it's not helpful to call this *just* a visual glitch. Unlike on a monitor, in a VR session, visual glitches cause considerable discomfort, especially when it's a discrepancy between eyes.

Zsolt Stefan (zsoltst) added a comment.Nov 23 2020, 2:46 PM

I've been playing around with the experimental XR-actions build, and this bug is still present.

With Viewport Denoising turned on, objects in the foreground cast a ghost on the background. As @Piotr Adamowicz (madminstrel) wrote, "just a visual glitch" is a big thing in VR, as your whole viewfield in VR is basically a HUGE 3D viewport.

Peter Kim (muxed-reality) mentioned this in D11858: VR: Fix for Viewport Denoising Artifacts.Jul 9 2021, 5:57 AM
Peter Kim (muxed-reality) mentioned this in rBc41b93bda532: XR: Fix for Viewport Denoising Artifacts.Jul 23 2021, 5:13 PM
Peter Kim (muxed-reality) closed this task as Resolved.Jul 23 2021, 5:15 PM
Peter Kim (muxed-reality) claimed this task.